JP2015148241A - Ball bearing cage and ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball bearing cage capable of maintaining a good lubricating property by supplying a proper amount of lubricant required for lubricating balls even during high-speed rotation while holding the lubricant, and to provide a ball bearing incorporating the cage.SOLUTION: A ball bearing cage 1 has a plurality of dimpled dents 6 formed in the inner peripheral face of each pocket 4 throughout its periphery, as recesses to function as lubricant reservoirs. The plurality of dents 6 linearly aligned at predetermined spaces in the radial direction are arranged at predetermined spaces in the peripheral direction of the pocket 4, and they are mounted with lubricant supply bodies, respectively. The opening width of each recess is 10 to 100 μm, the depth of the recess is 10 to 50 μm, a space between the recesses is 20 to 500 μm, and percentage of the area of the recess to the area of the pocket 4 is 5 to 50.

Description

  The present invention relates to a ball bearing retainer and a ball bearing in which the ball bearing retainer is incorporated. For example, the present invention relates to a ball bearing used for supporting an electric compressor, an electric blower, and an automobile motor.

  In recent years, electric compressors (electric turbochargers) have been developed by various companies in order to improve the efficiency of the internal combustion engine. As a bearing used for supporting the electric turbocharger, a grease lubricated bearing has been conventionally used since oil lubrication is structurally difficult.

  As shown in FIG. 5, the cage used in the grease lubricated bearing is formed with a groove 102 that functions as a grease reservoir on the inner peripheral surface of the pocket 101, and grease accumulates in the groove 102, whereby the ball surface A cage 100 is known that continues to supply grease. (See Patent Document 1.)

  Further, as shown in FIG. 6, a grease reservoir 112 continuous in the circumferential direction is provided on the inner peripheral surface of the pocket 111, and when the cage revolves, the grease is actively taken in and held in the grease reservoir 112, and the operation is continued. A cage 110 in which grease is supplied to the rolling element surface is known. (See Patent Document 2.)

JP 2007-315587 A JP 2008-106911 A

  By the way, the rotation speed of the bearing used for supporting the electric turbocharger is several tens of thousands to several tens of thousands of rpm. Therefore, the bearing running surface may be seized by not reaching the rolling element raceway surface. Further, as a countermeasure for stagnating the grease inside the bearing, a means for increasing the grease viscosity can be considered, but the bearing friction increases and the efficiency of the internal combustion engine decreases. In addition, even when the cages described in Patent Documents 1 and 2 are used, the above-described problems cannot be solved, and there is room for further improvement.

  The present invention has been made in view of the above-described problems. The purpose of the present invention is to hold a lubricant even during high-speed rotation and supply an appropriate amount of lubricant necessary for ball lubrication. An object of the present invention is to provide a ball bearing cage capable of maintaining lubricity, and a ball bearing incorporating the cage.

The above object is achieved by the following configuration.
(1) A ball bearing retainer comprising an annular portion and a plurality of pillar portions disposed at a predetermined interval, wherein a pocket for retaining a ball is formed between the adjacent pillar portions,
A recess functioning as a lubricant reservoir is provided on the inner peripheral surface of the pocket, the opening width of the recess is 10 to 100 μm, the depth of the recess is 10 to 50 μm, and the interval between the recesses is 20 to 20 μm. The ball bearing retainer according to claim 1, wherein the area of the recess is 5 to 50% with respect to the area of the pocket, and a lubricant supply body is mounted in the recess. (2) The ball bearing retainer according to (1), wherein a plurality of the concave portions are formed as dimple-shaped depressions.
(3) The ball bearing retainer according to (1) or (2), wherein a pair of claws for holding the ball protrude from an opening end facing the circumferential direction of the pocket. .
(4) The lubricant supplier is a lubricant-containing polymer comprising 20 to 40% by mass of polyethylene and the remaining 60 to 80% by mass of ester, PAO, ether or mineral oil. The ball bearing retainer according to any one of (1) to (3).
(5) The cage is made of any resin material of polyether ether ketone (PEEK), polyamide 66, polyamide 46, polyphenylene sulfide (PPS), and glass fiber is added to the resin material. The ball bearing retainer according to any one of (1) to (4).
(6) A ball bearing, wherein the ball bearing cage according to any one of (1) to (5) is incorporated, and the ball bearing cage is used under oil lubrication or grease lubrication.

  According to the ball bearing cage of the present invention, a recess functioning as a lubricant reservoir is provided on the inner peripheral surface of the pocket of the cage, the width of the opening of the recess is 10 to 100 μm, and the depth of the recess 5 to 100 μm, the interval between the recesses is 20 to 500 μm, the area of the recesses is 5 to 50% with respect to the area of the pockets, and the lubricant supply body is attached to the recesses, Lubricant that has oozed from the agent supply body adheres to the rolling surface of the balls and spreads on the raceway surface of the outer ring or the inner ring, thereby preventing seizure between the rolling surface and the raceway surface.

  Since the lubricant supply body is used only in the concave portion provided in a specific portion, not on the entire inner peripheral surface of the cage pocket, the lubrication performance can be maintained with a small amount of material and the material cost can be saved. .

(A) is a perspective view of the ball bearing retainer of the first embodiment according to the present invention, (b) is a partially enlarged view of (a), and (c) is an I of (b). -I is an enlarged sectional view. (A) is a perspective view of the ball bearing retainer of the second embodiment according to the present invention, (b) is a partially enlarged view of (a), and (c) is II of (b). It is -II expanded sectional view. (A) is a perspective view of the ball bearing retainer of the third embodiment according to the present invention, (b) is a partially enlarged view of (a), and (c) is III of (b). It is an expanded sectional view of the part. (A) is a perspective view of a ball bearing retainer according to a fourth embodiment of the present invention, (b) is a partially enlarged view of (a), and (c) is an IV of (b). It is -IV expanded sectional drawing. It is a perspective view which shows the holder | retainer of patent document 1 which formed the grease reservoir of the circumferential direction in the internal peripheral surface of a pocket. It is a perspective view which shows the holder | retainer of patent document 2 which formed the grease reservoir of the circumferential direction in the internal peripheral surface of a pocket.

Hereinafter, embodiments of a ball bearing retainer and a ball bearing according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1A is a perspective view of a ball bearing retainer according to the first embodiment of the present invention, and FIG. 1B is an enlarged perspective view of the vicinity of the pocket of the retainer. c) is an enlarged cross-sectional view around the concave portion of the pocket.
The ball bearing cage 1 of the present embodiment is applied to, for example, a ball bearing of an electric turbocharger motor, and is used under grease lubrication. The cage 1 includes a pair of annular portions 2 and a plurality of pillar portions 3 that connect the pair of annular portions 2 and are arranged at a predetermined interval, and between adjacent pillar portions 3, A cylindrical pocket 4 for holding the ball 8 is formed. On the outer peripheral surface of the cage 1, a pair of claws 5 for holding the balls 8 protrude from the opening end facing the circumferential direction of the pocket 4. The claw 5 extends from the outer peripheral surface side of the opening end toward the radially outer side, and the opposing surfaces of the pair of claws 5 are formed in a spherical shape that holds the balls 8.

  In addition, a plurality of dimples 6 having a circular shape in plan view are formed on the inner peripheral surface of the pocket 4 over the entire circumference as concave portions that function as a lubricant reservoir. The plurality of dimple-like depressions 6 are linearly arranged at predetermined intervals along the radial direction, and are arranged at predetermined intervals in the circumferential direction of the pocket 4.

  The plurality of dimple-like depressions 6 have an opening width W1 of 10 to 100 μm, a depth D of 10 to 50 μm, and a distance W2 of 20 to 500 μm. The area of the recess 6 is 5 to 50%, and the lubricant supply body 7 is mounted by adhesion or the like. If the area of the dimple-like recess 6 relative to the area of the pocket 4 is less than 5%, the lubricating performance is insufficient, and if it is more than 50%, the strength of the pocket inner peripheral surface is insufficient.

  The cage 1 is made of any resin material of polyetheretherketone (PEEK), polyamide 66, polyamide 46, or polyphenylene sulfide (PPS). Glass fiber may be added to the resin material.

The lubricant supply body 7 can be configured by absorbing or adsorbing the lubricant on a member that absorbs or adsorbs the lubricant, such as a porous member. For example, the lubricant supplier 7 is a lubricant-containing polymer in which polyethylene is 20 to 40% by mass, and the remaining 60 to 80% by mass is any one of ester, PAO (poly-α-olefin), ether, mineral oil, and the like. Consists of.
Further, with respect to the lubricant supplier 7, the lubricant and the lubricant absorbing member can be given temperature characteristics such that the lubricant oozes when it reaches a certain temperature. By giving such temperature characteristics, it is not necessary to exude unnecessary lubricant at a low temperature, and an increase in rolling torque of the bearing can be suppressed.

  In this embodiment, since the lubricant supply body 7 is held in the plurality of dimple-like recesses 6, the lubricant exuding from the lubricant supply body 7 adheres to the rolling surface of the ball 8. It is possible to spread over the raceway surface of the outer ring or the inner ring (not shown) and prevent seizure of the rolling surface and raceway surface.

As a result, even if the grease is exhausted or the grease does not reach the rolling surface of the ball or the raceway surface of the outer ring or inner ring, the lubricant can be stably stabilized. Can be supplied to the track surface.
In addition, since the dimple-like depression 6 can also collect grease, not only the lubricant but also the grease collected in the dimple-like depression 6 can be supplied to the balls.
In addition, since the electric turbocharger suddenly accelerates and decelerates, the use of the configuration of the present embodiment can prevent the temperature of the rolling surface of the rolling element from rising and seizing.

(Second Embodiment)
FIG. 2A is a perspective view of a ball bearing retainer according to a second embodiment of the present invention, and FIG. 2B is an enlarged perspective view around the pocket of the retainer. c) is an enlarged cross-sectional view around the concave portion of the pocket.
In the ball bearing retainer 1a of the present embodiment, as in the first embodiment, a plurality of dimple-like recesses 6a are formed on the inner peripheral surface of the pocket 4 as recesses that function as a lubricant reservoir. The dimple-like recess 6a according to the embodiment is formed in an oval shape in a plan view and an arc shape in a cross-sectional view. Also in this case, the dimple-like recess 6a has an opening width W1 of 10 to 100 μm, a depth D of 10 to 50 μm, and each interval W2 of 20 to 500 μm. The area of the recess 6a is 5 to 50%, and the lubricant supply body 7 is mounted.
Unlike the first embodiment, the cage 1a of the second embodiment and the cage 1b of the third embodiment described later and the cage 1c of the fourth embodiment are configured without having claws on the outer peripheral surface. Has been. Other configurations and functions are the same as those in the first embodiment.

(Third embodiment)
FIG. 3A is a perspective view of a ball bearing retainer according to a third embodiment of the present invention, and FIG. 3B is an enlarged perspective view around the pocket of the retainer. c) is an enlarged view of the periphery of the recess of the pocket.
In the ball bearing cage 1b of the present embodiment, a plurality of grooves 6b extending in the radial direction of the cage 1b are formed on the inner peripheral surface of the pocket 4 as recesses that function as a lubricant reservoir. The groove portions 6b are provided at a predetermined interval in the circumferential direction of the pocket 4, and are continuous from the inner peripheral surface side opening periphery of the pocket 4 to the outer peripheral surface side opening periphery. The groove 6b has an opening width W1 of 10 to 100 μm, a depth D of 10 to 50 μm, each interval W2 of 20 to 500 μm, and the area of the groove 6b with respect to the area of the pocket 4 is 5 to 50. %, And the lubricant supply body 7 is mounted.
Other configurations and functions are the same as those in the first embodiment.

(Fourth embodiment)
FIG. 4A is a perspective view of a ball bearing retainer according to a fourth embodiment of the present invention, and FIG. 4B is an enlarged perspective view around the pocket of the retainer. c) is an enlarged cross-sectional view around the concave portion of the pocket.
The ball bearing retainer 1c of the present embodiment has a plurality of grooves 6c extending over the entire circumference on the inner peripheral surface of the pocket 4 as concave portions that function as a lubricant reservoir. The groove 6c has an opening width W1 of 10 to 100 μm, a depth D of 10 to 50 μm, each interval W2 of 20 to 500 μm, and an area of the groove 6c with respect to the area of the pocket 4 is 5 to 50. %, And the lubricant supply body 7 is mounted.
Other configurations and functions are the same as those in the first embodiment.
Further, instead of the groove 6c, a groove that spirally extends over the entire circumference on the inner peripheral surface of the pocket 4 may be used.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
For example, the cage may be provided with chamfers in various places as necessary, and the chamfering facilitates the processing of the cage and prevents the balls from being damaged at the edge portion of the cage.

The shape of the inner peripheral surface of the pocket is not limited to the cylindrical shape of the present embodiment, and may be a spherical shape.
In the above embodiment, the ball bearing is used under grease lubrication, but may be used under oil lubrication.
Further, as the ball bearing, a deep groove ball bearing or an angular ball bearing in which the ball is located at the center in the axial direction can be applied.
In addition, the cage is not limited to that of the present embodiment as long as it is a resin cage, and may be, for example, a crown type cage.

The ball bearing cage of the present invention and the ball bearing in which the ball bearing cage is incorporated can be suitably used for supporting an electric compressor, an electric blower, and an automobile motor.

1, 1a, 1b, 1c Cage 2 Ring part 3 Column part 4 Pocket 5 Claw 6, 6a Indentation (recessed part)
6b, 6c Groove (recess)
7 Lubricant supply body

Claims (6)

A ball bearing retainer comprising an annular portion and a plurality of pillar portions arranged at a predetermined interval, wherein a pocket for holding a ball is formed between the adjacent pillar portions,
A recess functioning as a lubricant reservoir is provided on the inner peripheral surface of the pocket, the opening width of the recess is 10 to 100 μm, the depth of the recess is 10 to 50 μm, and the interval between the recesses is 20 to 20 μm. The ball bearing retainer according to claim 1, wherein the area of the recess is 5 to 50% with respect to the area of the pocket, and a lubricant supply body is mounted in the recess.   The ball bearing retainer according to claim 1, wherein a plurality of the concave portions are formed as dimple-shaped depressions.   The ball bearing retainer according to claim 1 or 2, wherein a pair of claws for holding the ball is protruded from an opening end facing the circumferential direction of the pocket.   The lubricant supply body is a lubricant-containing polymer comprising 20 to 40% by mass of polyethylene and the remaining 60 to 80% by mass of ester, PAO, ether or mineral oil. The ball bearing retainer according to any one of claims 3 to 4.   The retainer is made of any resin material of polyether ether ketone (PEEK), polyamide 66, polyamide 46, polyphenylene sulfide (PPS), and glass fiber is added to the resin material. The ball bearing retainer according to any one of claims 1 to 4.   6. A ball bearing comprising: the ball bearing retainer according to claim 1, wherein the ball bearing retainer is used under oil lubrication or grease lubrication.

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